Extensible hoist



Aug. 22, 1967 J. D. SUMNER EXTENSIBLE HOIST 4 Sheets-Sheet 1 Filed Aug.13, 1965 (foe .0. Jam/76m JNVENTOR.

BY f i ATTORNEY Filed Aug. 13, 1965 JIVI'ERMED/ J. D. SUMNER EXTENSIBLEHOIST 4 Sheets-Sheet 2 (/0 e fl Jam/Yer INVENTOR.

ATTOFA/EV Aug. 22, 1967 J- D. SUMNER 3,337,187

EXTENSIBLE HOI ST Filed Aug. 13. 1965 4 Sheets-Sheet 3 J0 e .0. Jam/7 erINVENTOR.

ATTORNEY 1967 J. 1::' SUMNER 3,337,187

EXTENSIBLE HOI ST Filed Aug. 13, 1965 4 Sheets-Sheet 4 J09 .5. Jam/7e)"INVENTOR.

ATTOR/VE V United States Patent Office 3,337,187 Patented Aug. 22, 1967This invention relates to hoisting mechanism and more particularly tohoisting apparatus embodying telescoping extension means for adjustingthe height of the load which is supported.

The invention has for an important object the provision of hoistingmechanism which is easily moved about for use at any desired locationand by which the load which is lifted may be readily moved from place toplace.

Another object of the invention is to provide hoisting mechanism whichis supported to be rolled about and embodying means for stabilizing thestructure against overturning.

A further object of the invention is the provision in hoisting mechanismof a telescoping, extensible, upright standard or mast supported on abase having wheels disposed in radially spaced relation to the axis ofthe standard or mast, and means for supporting a load on the standard ata substantially centralized location relative to the wheels to increasethe stability of the mechanism.

Another object of the invention is the provision in extensible hoistingmechanism of an upright mast or standard which is formed of a number oftelescopingly arranged, tubular members having roller means positionedto hold the members in axial alignment during relative longitudinalmovement of the members and means for imparting such relativelongitudinal movement to the members to extend the same.

A further object of the invention is the provision in hoisting mechanismof the type having an upright standard or mast formed of telescopinglyarranged tubular members, of cable mechanism for simultaneouslyextending inner ones of said members relative to each other and relativeto the outermost member thereof to increase the height of the standard.

A still further object of the invention is to provide hoisting mechanismwhich is of simple design and rugged construction and which may beeconomically manufactured.

The above and other obvious objects and advantages of the invention willbe apparent from the following detailed description of a preferredembodiment of the mechanism when considered in conjunction with theannexed drawings, wherein:

FIGURE 1 is a side elevational view, partly broken away and partly incross-section, illustrating the hoisting mechanism of the invention andshowing the same in a substantially fully retracted position;

FIGURE 2 is a cross-sectional view, taken along the line 22 of FIGURE 1,looking in the direction indicated by the arrows;

FIGURE 3 is a cross-sectional view taken along the line 33 of FIGURE 1,looking in the direction indicated by the arrows;

FIGURE 4 is a fragmentary, perspective view of the cable mechanism bywhich the telescoping members of the upright standard or mast of themechanism are operated, showing the cable mechanism removed from thesurrounding structure of the hoisting mechanism and with the parts inthe positions which they occupy when the telescoping members areretracted;

FIGURE 5 is a View similar to that of FIGURE 4, showing the parts of thecable mechanism in the positions which they occupy when the telescopingmembers are extended, illustrating the manner in which the height of thestandard or mast is increased;

FIGURE 6 is a cross-sectional view on an enlarged scale taken along theline 66 of FIGURE 1, looking in the direction indicated by the arrows;

FIGURE 7 is a cross-sectional view on an enlarged scale, taken along theline 7--7 of FIGURE 1, looking in the direction indicated by the arrows;

FIGURE 8 is a cross-sectional view on an enlarged scale, taken along theline 88 of FIGURE 1, looking in the direction of the arrows;

FIGURE 9 is a cross-sectional view on an enlarged scale, taken along theline 9-9 of FIGURE 1, looking in the direction indicated by the arrows;and

FIGURE 10 is a cross-sectional view on an enlarged scale, taken alongthe line 1010, looking in the direction indicated by the arrows.

Referring now to the drawings in greater detail the hoisting mechanismof the invention includes a base or supporting frame made up ofelongated frame members 10, 10 and v12, 12 whose inner ends are securedto a connector plate 14, or the like, the members diverging outwardlyfrom the plate in the same horizontal plane and having their outer endspositioned in a substantially rectangular arrangement. The members maybe secured to the plate 14 by any suitable means, such as welding andeach member is supported at its outer end by a wheel or caster 16mounted for swivelling movement about a vertical axis to allow thestructure to be easily rolled about in any direction.

The hoisting mechanism includes an extensible upright standard or mast,generally designated 18, formed of telescopingly arranged, elongated,tubular elements of generally rectangular shape in cross-section, theoutermost one, 20, of which extends through the plate 14 and is attachedthereto near its lower end. The lower end of the element 20 is connectedto the member 10, 10 and 12, 12 by braces 22 and 24, as shown in FIGURE1, as by means of welding or the like. The mast 18 is thus held rigidlyupright at a location somewhat offset to one side of the center of thebase.

The mast or standard 18 has an intermediate tubular element 26 whichtelescopes within the element 20, and an inner element 28 which istelescopingly disposed in the element 26. Thus, the outermost element 20is stationary on the base while the intermediate element 26 and innerelement 28 may be extended upwardly relative thereto and the innerelement 28 may be extended upwardly relative to the element 26.

At its upper end, the inner element 28 carries a cross arm 30 upon whoseopposite ends pulleys 32 and 34 are rotatably mounted for rotation onhorizontally disposed axes. The pulley 32 is thus supportedsubstantially vertically above the center of the supporting base.

Suitable cable winding mechanism is mounted on the outer element 20,which may be of the type having two winding drums or reels 36 and 38,provided with handles, as shown at 40 and 42, and which also havesuitable ratchet or detent mechanisms, designated 44 and 46,respectively, of a usual type to permit the reels to be wound in onedirection while preventing unreeling movement of the same. The detentmechanisms are constructed to be released when desired to allowunreeling of the winding mechanisms.

The reel 36 has a cable 48 wound thereon which extends upwardly, overthe pulleys 32 and 34 and downwardly centrally above the base, and isprovided at its free end with a load supporting hook 50, of the usualkind, and a weight 52 to assure the lowering of the hook when the reel36 is released for unwinding. Thus by connecting the hook 50 to a loadto be lifted, the cable 48 may be wound up to lift the load and supportthe same in a substantially centralized position relative to the base.

The tubular elements 20, 26 and 28 are shaped as shown, the outerelement 26 being somewhat wider and longer in cross-section than theintermediate element 26, which in turn is somewhat wider and longer incrosssection than the inner element 28, whereby the elements may betelescopingly arranged, and space is provided between the elements forthe cable mechanism by which the elements are extended and retracted.

For the purpose of extending and retracting the intermediate and innerelements of the mast or standard, the intermediate element 26 has apulley 54 rotatably mounted thereon near its lower end inside of theouter element 20, and the outer element has an external pulley 56mounted on a horizontal shaft 58, rotatably carried on brackets 60attached to the upper end of the outer element. A cable 62 extends aboutthe pulleys 54 and 56 and is anchored at one end to a cylindricalextension 64 of the pulley 56, surrounding the shaft 58, which cable iswound on the reel 38, so that upon Winding up of the cable 62 theintermediate element 26 will be extended upwardly and upon unwinding ofthe cable the intermediate element will move downwardly in the outerelement.

A pulley 66 is rotatably mounted on the inside of the intermediateelement 26, inner element 28, near its lower end, and the intermediateelement 26 has a pair of pulleys 68, 68 rotatably mounted on brackets69, 69 on the upper end of the intermediate member, and a cable 70passes about the pulley 66 and over the pulleys 68, 68, as shown inFIGURES 4 and 5, and is attached to the cylindrical extension 64 by eyesor loops 72, so that upon extension of the intermediate element 26 bythe winding up of cable 62, cable 70 will be operated to extend innerelement 28 simultaneously with the intermediate element.

For the purpose of holding the tubular elements in longitudinalalignment, as shown, to maintain the elements in properly spacedrelation to accommodate the pulleys 54 and 66 between the elements andprovide space for the cables 62 and 72, the outer element has a roller74 rotatably mounted between the brackets 60, 60 as shown in FIGURE 7which bears against an outer face of the intermediate element 26, andthe intermediate element has a roller 76 rotatably mounted thereonadjacent its lower end which bears against an inner face of the outerelement to hold these elements in longitudinal alignment in all relativelongitudinal positions of the elements. Similarly, the inner element 28carries at its lower end an externally mounted roller 78 positioned forengagement with an inner face of the intermediate element 26, and theintermediate element also carries a roller 80, shown in FIGURE 6,rotatably mounted on the brackets 69, 69, in position for engagementwith an outer face of the inner element, to hold the intermediate andinner elements in the same position of longitudinal alignment in allrelative longitudinal positions of the intermediate and inner elements.By this arrangement the elements are prevented from tilting relative toeach other when extended, thus avoiding any tendency of the elements tobind against each other.

The intermediate element 26 may also be provided with external guidingor spacing members 82, 82 at its lower end extending along oppositesides of the element in position for sliding engagement with opposite,internal, side surfaces of the outer element to hold the intermediateelement centralized laterally therein.

In making use of the hoisting equipment, constructed as described above,the base frame may be rolled up to and object to be lifted and the cable48 unwound to allow the hook 50 to be hooked to the load, whereupon thecable may be wound up to lift the load and suspend the same in aposition substantially centered above the frame.

With the load thus suspended, the hoist may be rolled to any desiredlocation. Because of the centering of the load with respect to thewheels 16, the stability of the device is greatly enhanced, so thatthere is little or no danger of overturning the equipment.

When it is desired to elevate the load, this may be accomplished bywinding up the cable 62 which extends the intermediate element 26,whereby the cable 70 and pulleys 68, 68 are actuated to extend the innerelement 28. During extension of the mast the inner element 28 will beextended relative to the intermediate element as the intermediateelement is extended relative to the outer element, thus providing anarrangement which is very steady and stable in operation and which maybe very easily and quickly adjusted to any desired height. Due to thecable and pulley arrangement by which the mast is extended, the closefitting of the inner element 26 laterally in the intermediate element,and the roller guiding and spacing means provided for the elements,relatively heavy loads may be rapidly elevated without wobbling or looseplay.

The invention thus provides extensible hoisting mechanism which is ofsimple design, string and rigid construction and which is easy tooperate.

The invention is disclosed herein in connection with a particularembodiment of the same, which is intended by Way of illustration only,and it will be apparent that various modifications can be made withinthe spirit of the invention and the scope of the appended claim.

Having thus clearly shown and described the invention, what is claimedas new and desired to secure by Letters Patent is:

Hoisting apparatus comprising a supporting frame, an outer, elongated,tubular element fixedly attached at its lower end to the frame andextending upwardly therefrom, an intermediate, elongated, tubularelement in and movable longitudinally in the outer element, an inner,elongated, tubular element in and movable longitudinally in saidintermediate element, all of said elements being of generallyrectangular shape in cross-section, an upper, elongated roller rotatablycarried on the outer element adjacent the upper end thereof in rollingengagement with one side face of said intermediate element, a lowerelongated roller rotatably carried on said intermediate element adjacentits lower end in rolling engagement with the side face of said outerelement remote from said one side face of said intermediate element, anupper, elongated roller rotatably carried on the intermediate elementadjacent its upper end in rolling engagement with one side face of saidinner element, a lower, elongated roller rotatably carrier on said innerelement adjacent its lower end in rolling engagement with a side face ofsaid intermediate element remote from said one side face of saidintermediate element, said rollers being positioned for coaction withthe elements to hold said intermediate and inner elements againsttilting movement relative to said outer element, means positioned forcoaction with the elements to move said intermediate elementslongitudinally relative to said outer element and to each other to varythe height of the standard and means on said inner element positionedfor engagement with a load to support the load in an elevated position.

References Cited UNITED STATES PATENTS 1,428,887 9/1922 Hescock 254139.11,789,025 1/1931 Shepard 254139.1 2,419,813 4/1947 Berchtold 254139.12,632,530 3/1953 Wagner 254-143 2,877,868 3/1959 Gunning 1879 2,946,4067/1960 Henry 1879 FOREIGN PATENTS 592,469 2/ 1960 Canada.

EVON C. BLUNK, Primary Examiner.

H. C. HORNSBY, Assistant Examiner.

